Carpathite
| Carpathite | |
|---|---|
Carpathite from New Idria District, California USA | |
| General | |
| Category | Organic mineral |
| Formula | C24H12 |
| IMA symbol | Cpa |
| Strunz classification | 10.BA.30 |
| Crystal system | Monoclinic |
| Crystal class | Prismatic (2/m) (same H-M symbol) |
| Space group | P21/c, P21/n |
| Unit cell | a = 1625 pm, b = 463.8 pm, c = 1042 pm; β = 111°10'; Z = 2 |
| Identification | |
| Color | Yellow, yellowish brown on exposure |
| Crystal habit | Acicular to thin tabular in bladed groups and fibrous radiating aggregates |
| Cleavage | Perfect on [001], [100] and [201] |
| Fracture | Splintery |
| Tenacity | Flexible, nearly plastic |
| Mohs scale hardness | 1.5 |
| Luster | Vitreous - adamantine |
| Streak | Yellow white |
| Diaphaneity | Transparent |
| Specific gravity | 1.35 |
| Optical properties | Biaxial (+/-) |
| Refractive index | nα = 1.760 - 1.780 nβ = 1.977 - 1.982 nγ = 2.050 - 2.150 |
| Birefringence | δ = 0.290 - 0.370 |
| Melting point | 432.8 °C |
| Other characteristics | Fluorescent - electric blue to blue-green |
| References | |
Carpathite is a very rare hydrocarbon mineral, consisting of exceptionally pure coronene (C24H12), a polycyclic aromatic hydrocarbon. The name has been spelled karpatite and the mineral was improperly renamed pendletonite.